Furnace door



Aug. 8, 1944.

W. C. BULMER FURNACE DOOR Filed April 1, 1942 HPH I w INVENTOR ATTORNEYS Patented Aug. 8,

FURNACE DOOR William Bulmer, Aspinwall, Pa., assignor to Reliance Steel Products Company, McKeespoi-t, Pa., a corporation of Pennsylvania;

Application April l, 1942, Serial No. 437,161

3 Claims. ((1.122-498) This invention relates in general to the furnace art and is particularly applicable to furnace doors of the water coolecLmetal frame, refractory faced type. These doors are used in furnaces, such as steel open hearth furnaces wherecomparativel high temperatures are. encountered. j

One of the disadvantages inherent in certain types of water cooled furnace doors in-comrnon use is the difficulty of readily determining the condition of the refractory lining which is exposed to the high' temperatures encountered in melting and refining steel. In-other types of furnace doors where considerable areas of refractory lining are visible from outside the'door the operators are exposed to considerably more heat than is desirable.

By my invention I provide a door of such con-- struction that the operator by rapid inspection, can determine the condition of the door lining and at the same time is exposed to relatively little heat. This I accomplish by providing a series of water cooled-inspection holes spread over the furnace door area. By glancing through these holes the lining can be inspected and the need for relining determined.

It is also an object of my invention to provide a novel and very effective bracing arrangement for strengthening the door structure and which is such as to avoid impairment ,of the circulation of the fluid employed to cool the door and which presents no sediment retaining-surfaces.

In the accompanying-drawing, wherein I have shown for purposes of illustration only a preferred embodiment of my invention:

Fig. I is a plan view showing the door in rear elevation, but with part of the refractory lining broken away, and

plates 3 and l. A statically balanced dumb-bell shaped wicket cover I0 is swivelly attached at l l to the outer plate3. The cover can be swung into position to cover or uncover the wicket hole 9.

In'the main panel portions of the plates 3 and 4 (those portions whichenclosethe main water space 5) I provide spaced apart alined openings,

the edges of. which openings are welded to the ends of short pieces of metaltubing l2 which I extend between the plates. This construction provides a series of "water cooled tell-tale aper-' tures or inspection openings [3 through which the condition of the refractory lining 8, which closes the holes I3 can be viewed.

' The tubes I2 are shown as round in section, but it is evident that the tubes'ofother sections such as square, diamond, or even rectangular could be used, Whatever shape-is used, the tubes should be so placed as to present as small .an area as possible on which sediment could gather. Thus if a triangular shaped tubeis used it should preferably be placed so that the base will be at the lower part of the opening.

It will be observed that the construction does not include the customary. stay bolts between the innerand outer plate; Such stay-bolts are Fig. II is a. view in vertical section along .the line water space 5 and a peripheral water space 6,1

around the edge of the door. The space- 6 projects inwardly from the main water space 5.

The back or inner plate 4-is shapedjso' as'to provide a reentrant space or recess 1, in which a refractory lining 8, usually of fire brick is piaced.

, tteHromTthespace in line Jwlth a wicket hole unnecessary since the tubes l2 themselves are effective stay-bolts.

I prefer to locate the inspection holes so that any hole is not much over one foot from another one. At the middlepart of the door I prefer somewhat closer spacing, as this is the area where the refractory lining generally disintegrates most rapidly and therefore should be moreclosely inspected.

A water inlet pipe l4 extends from one corner of the frame into the side portion of the peripheral water space 6 to a point-near the bottom of the water space 6. An outlet pipe I5 is provided. at the opposite upper corner. Lifting lugs iii are provided at the top of the door.

While I have shown theinner plate 4 as dished and the, outer plate 3 as fiat, it is to be understood that both plates may be flat or both dished, and

that either one may be dished and the other flat.

It is also possible to cast such a door.

By my invention I provide a water. cooled fur-- nace door, which is relatively cool and conse quently protects (the workmen from excessive heat, is sturdy in construction. inexpensive to fabricateand one inwhiclilthecondition of the refractory lining is at all times visible.

9 which extends through-the as While I have illustrated and describeda preferred embodiment of my invention, it will be I understood that it not limited thereto. but may be otherwise embodied and practiced within the scope of the following claims.

I claim as my invention:

1. A water cooled furnace door including an outer plate and an inner plate spaced from the outer plate, the plates enclosing a water space, said outer plate having a plurality of spaced apart openings, said inner plate having corresponding and aligned openings, tubes extending from one plate to the other and secured to the portions of the plates surrounding the openings, said door'having a refractory lining adjoining the inner plate.

2- In a water cooled furnace door including an outer plate, an inner plate, said plates enclosing a space, and a refractory lining for said inner plate, the invention which consists of hollow stays connected to and extending between said plates and providing an inspection opening through the plates and through which the refractory lining may be viewed.

3. In a water cooled furnace door including .an outer plate, an inner plate, said plates enclosing a space, and a refractory lining for said inner plate, the invention which consists of a plurality of tubular members connected to and extending between and through said plates and providing an inspection openingthrough the plates and through which the refractory linng' may be viewed.

4. In a water cooled furnace door including spaced apart walls lined with a refractory, the invention which consists of a plurality of tubular members extending between and integrated to said walls the bores of said tubular members extending through said walls and providing inspection openings through which the refractory lining may be viewed.

5. A water cooled furnace door having a water extending crosswise ofthe chamber and through the opposite walls thereof.

6. A water cooled furnace door including a front plate and a back plate spaced from the front plate, the back plate having a portion bowed toward the front plate, the plates enclosing a.

water space, a plurality of spaced openings in the bowed portion, the front plate having corresponding aligned openings, tubes extending from one plate to the'other and secured to the portions of the plates surrounding the openings and a refractory lining extending rearwardly from the back plate.

7. A water cooled furnace door including a front plate and a back plate spaced from the front plate, the back plate having a portion bowed toward the front plate, the plates enclosing a water space, a plurality of spaced openings in the bowed portion, the front plate having corresponding'aligned openings, tubes extending from one plate to the other and secured to the portions of the plates surrounding the openings and a refractory lining of substantially uniform thickness, extending rearwardly from the back plate 8. In afurnace door including a double walled structure provided with a heat-resisting facing and forming between the walls a cooling space, said walls having a plurality of spaced openings, with the openings in one wall aligned with the openings in the other wall, the invention which comprises a plurality of tubes secured to and extending between said Walls at the aligned openings therein to provide for inspection of said facing.

WILLIAM C. BULMER. 

